Could also be the game developers weren't given much insight into the movie before it was out to avoid leaks. They knew there would be a Rey and unmasked Kylo, obviously. Maybe they had to actually wait until the movie came out to consider which characters would be best to add.
Although, tbh, I can't think of any characters from TLJ that I absolutely wanted added, other than Rey JT and KRU and Praetorian Guard. Possibly Jedi Master Luke, I suppose. Finn, Poe, and Phasma didn't really change enough to warrant new toons in-game, imo. And the rest of the cast was pretty meh, imo. I'm certain we'll get a Rose, maybe even a Holdo, but hopefully we won't have to re-hash the other toons.
And also consider Rey JT is gated behind a massive pay-wall and/or time-grind. If you were a new player coming to this game and jonesing to have a Rey JT in a squad... what would you do if you realized it would take months to fulfill the BB8 requirements, as well as collect the Veterans and all that? So... saying that, to say, I'm not sure the gamemakers are actually marketing toward new players as much as we think.